Repairing Single Handle Faucet
There are four different types of faucets: ceramic disk, cartridge, rotating ball and compression. After you have determined which type of single handle faucet you have, then you can begin repairing it.
Disk and cartridge Faucets
A ceramic disk faucet has two ceramic disks that control water flow. To repair a disk faucet, the water must be turned off first with the shutoff valve located in the basement near the water heater. The disk faucet should be disassembled by first popping off the plastic cap on the handle with a flat-head screwdriver. A faucet handle can be removed by loosening the single screw with a flat-head screwdriver. The disk will be held in place with two screws, which can be removed with a screwdriver. After the screws are removed, the ceramic disk can be will easily slide out with just your fingers. With just a slight push of the fingers, the new disk will lock into place. The faucet can be reassembled in the reverse order it was taken apart.
A cartridge faucet is composed of a single cartridge that monitors and controls water flow and temperature. First, the water supply should be turned off with the main water valve. The plastic cap on the handle can be removed with a flat-head screwdriver. After the screw is revealed beneath the cap, it can be removed with a screwdriver. The faucet handle should easily come off and will reveal a sleeve that holds the cartridge in place. Needle-nose pliers or a screwdriver can help remove the sleeve. After the sleeve is removed, the cartridge can be removed with pliers. A new cartridge can slide right into the spot where the old one was. The faucet can be reassembled in the reverse order it was removed.
Rotating Ball Faucet
Ball faucets consist of a round ball above the base of the faucet. Before beginning any work, the water supply needs to be shutoff. The entire faucet has to be disassembled to repair it by popping off the plastic cap on the handle with a flat-head screwdriver. The faucet spout can be pulled off with your fingers, which will reveal the cam and seals underneath. A pair of needle-nose pliers can aid in removing the cam and washer. The ball, seals and springs should be replaced with new parts if they are worn. Reassembling the faucet can be done in the reverse order it was removed.
A compression faucet contains a washer compressed against the valve seat. After the water supply is turned off with the main shutoff valve, the plastic cap on the handle can be removed with a flat-head screwdriver. A flat-head screwdriver can help remove the single screw in the handle and the handle will easily lift off after this. The retaining nut will then be revealed, which can be removed with an adjustable wrench. Needle-nose pliers will aid in removing the threaded stem, which will reveal the O-ring and stem washer beneath it. The O-ring and washer should be replaced with new parts. Reassembling the faucet can be done in the reverse order you removed them.
All worn or defective parts in the faucets should be replaced or the problem may not be fixed. If you are unsure which part to purchase, then bring it to a hardware store to match it up.